Train control



NOV. 1, 1932. I J SPRAGUE 1,886,062

TRAIN CONTROL Filed June 12, 1928 64 60 BY 9 6k 61 63 A TTORNEYS.

Patented Nov. 1, 1932 PATENT OFFI FRANK JULIAN srnaenn, or new YORK, n. Y.

TRAIN CONTROL Application Cfiled June 12,

. My invention relates to train controlsystems and more particularly to the. disposition of traclrway devices and their coopera tion with car-carried train control apparatus used in train control systems of the/ intermittent inductive type. v v Various arrangements of the trackway devices have been suggested for such systems in the past, one being fully disclosed in my British Patent 149,922. In said patent use is made-fof track elements of two varieties, namely, application track elements, which transmit impulses to actuate or initiate actuation of normally inactive vehicle-carried train control apparatus and reset track elements, which transmit impulses to restore or permit restoration of the train control apparatus after their actuation.

' In the patent just referred to both the application and the resetftraclr elements are traific controlled, and the primary object of my present invention is to provide for track elements of such character and disposition'that traflic' control is required for one kind of track element only.

Another object of my invention is to provide for traclrway devices which transmit an impulse at every control point, irrespectiveo'f trafiic conditions, and thereby initiate actuation of the vehicle-carried apparatus, and check the integrity of the application track elements as well as of the translating device of the vehicle-carried apparatus every time a vehicle passes a control point, but cause automatic brake application only ifadverse traliic conditions exist ahead of the train when the control point is passed.

Other objects and advantages of my invention shall appear as the description progresses and shall be particularly pointed out in the appended claims.

Referring to the accompanying drawing in which'corresponding parts are designated by similar marks of reference Figure 1 is a diagrammatic representation of a control system illustrating my invention; at the bottom of the figure a track is shown with trackway instrumentalities illustrating one form of my invention; above this are shown the vehicle-carried parts.

scit iron pole pieces5-and the reset track element is an electro magnet with a coil 6, a core a reset portion, these portions being disieza. Serial No. 284,801.

"Fig. 2 is a diagrammatic illustration ofa track with trackway'instrumentalities showmg another form of my invention and also indicating the receiver of the vehicle apparatus Fig. 3 is a diagrammatic showing of the receiver of Figs. land 2 on a larger scale. f

V Fig; 4 is ajschematic diagram illustrating time delayineans empl oyable withmy appa ratus.

Rei erring'to Fig. lithere is shown a sectien of a railroad track divided by insulated oints 1 into blocksin' theusualimanner. Eachblock is'provided with a track relayQ at one end, and a source of energy, wliichhas been illustrated as a battery 3, at the other enc. 1

Placed near the end of each block is a permanently active application track element A closely followed by a trafiic controlled reset track element R. v I i 1 i e As illustrated in Fig, 1, the application track element is a permanent magnet 4 with 7: and pole pieces 88. The energizing circuit for the reset magnet R includes abattery 9 and a-c'ontact 1O controlled by the track relay 2. It should be understood that the herein presented simple form of trailic control for the energizing circuit of the reset magnets is merely indicative, and thatas a rule such control requires additional instrumentalities and more involved circuit arrangements. As the organization of such circuits and instrumentalities is well known in the art, a simple showing has been selected here for clearness of understanding, thereby also omitting all instrumentalities which as, for instance, wayside signals, may be adjunctto the train control system.'

Suitably carried on the vehicle isa double receiver 1) comprising an application and 95 posed in such angular positions as to cooperate with the respective track magnets, and will be hereafter referred to as the application receiver and the reset receiver. lVhi'le these two receivers are here shown combined tion 11-12 of magnetic material, interrupted b a 20, and rovided at its two ends with c llec plates l 13. Projections 20'20' of thd" portion 11-12 form poles in close proximity whereof is pivoted a spring retracted armature 15.

The reset receiver comprises a portion 16-17 of magnetic material, interrupted by a p 21 and provided at its two ends with co lector plates 18-18. Projections 21-21' Qffllfl ion 16-47 form poles in closeprox- "hereof is pivoted a spring retracted l 1 'edf 0, ae an im use recelv rom mtiafi ii? to govern urther train control Wows, there is rovided a normally enstick'relay 'Ihe maintaining cir- 13,11,116 i relay includes the stick-armature Qfi'dfift'he relay S, and the application armatitre 15. The circuit can be traced as follows: From the plus side of a battery 22, or an suitable source of electric energ), t roug a wire 23, contact and armature 15 of the a fllcatio'n receiver, a wire 24, stick-armature 2, and contact 27 thereof, a wire 28, coil 29 of relay S, and a wire 30 back to negative batiThe further traincontrol apparatus is reprefinted by a device K shown as a normally energized electromagnet, the energizing circhit of which is controlled by an armature Ofthe stick relay. The device K may be, in a simple train control system a device, de-energizati n of which directly results in an automatic brake application, or in a more complete system, it ma represent a device which merel governs urther train control apparatus; ereby the brake applying means 6 I y i the automatic brake appllcation may either the standard engineers valve or a $6 arate brake valve.

H rres tive thereof, if the magnet K is the bra controlling device proper, or only anintermediate device, I provide a time de- 21g between the de-energization of the mag- "K and the actual ap ication of the brakes {brother actuation of t e train control apparatus tending to restrict the movement of the vehicle). Such time delay may be obtained by pneumatic, magnetic, or other suitable means. As an exemplification of such time delay means there is shown in Fig. 4 a device I which comprises an electro-magnet E having a coil surrounded by an iron cylinder 5t and a plunger type armature 52 which is preferably of conical shape.

7 Slackly suspended on the plunger 52 is a piston 53 movin within a hollow cylinder 54 which is integra with or forms an-extension of the cylinder 51. A small bore 55 goin through the piston 53 provides for the slow equalization of the air pressure below and above the piston as the precise fit of the piston 53 in the cylinder 54 practically prevents communication between the space above and below the piston 53 along this piston.

The cylinder 54 is closed on its bottom by a discwhich carries a spring contact 61 and a cooperating top contact 62, the contacts 61 and 62 being provided with leads 63 and 64 through the disc 60. The piston 53 carries a stop 65. p

Wm the magnet K is energized the plun er 52 is attracted and the piston 53 lifted. The spring contact 63 contacts against the contact 62 and closes the circuit of a second electro-magnet K-2 through the battery 22 or any other suitable source of six y.

This electro-magnet K-2 is now the brakecontrolling device proper, upon de-energizatilozdof which the brakes are immediately app Whenever the electro-magnet K is de-energized the piston 53 drops slowly as it compresses in its descent the air underneath, as the pressure on the two sides of the piston can only gradually equalize through the bore 55. B suitably dimensioning bore 55 time delays 0 a fractlon of a second to several seconds ma be obtained.

e energizing circuit of the device K is as follows:

From plus battery through a wire 31, coil 32 of the device K, a wire 33, contact 34 and armature 35 of the relay S back to negative battery.

There are also two normally open circuits shown in Fig. 1. One circuit hereafter referred to as the reset circuit, goes from plus battery through wire 23 to the reset armature 19, is broken at a contact 19' (cooperating with armature 19) from where it can be traced through a wire 36, coil 29, and wire 30, to negative battery.

The other normally open circuit goes from plus battery through a wire 37 to an indicating device 38 (which may be visible or audible, or both), and from there through a wire 39 to a back contact 40 of armature 35; this circuit is completed to the negative side of the battery, when, the armature 35 is in its down position due to de-energization of the stick relay.

centrifugal speed governor 46 is indicated as controlling the armature 45. When the armatune v35 drops upon receipt of a track impulse, the energizing circuit of the device K g is maintained through contact 45 provided the speed of the train is below a set limit.

Instead of providing a time delay between the de-energizationof the device K and the actuation of the brakestor other train control apparatus) a time interval maybe provided between the de-energization of the stick relay S and the de-energization of thedevice K, which can be obtained for instance by making the control armature 35 slow-acting.

In this case, however, the indicating device 38 should be controlled by another armature than the slow-acting armature 35 to display the indication immediately upon receipt of the trackimpulse.

Operatiow JNhen a train reaches the end of a block, it first passes a permanent application magnet A. An application impulse is thereby transmitted from the track-irrespective of traiiic conditionswhich causes the poles 2020 to attract the armature 15 and to intermittently break the contact 15-15 in the maintaining circuit of the stick relay S. )V hen the magnet ispassed the spring returns the armature 15 to its normal position. 7

However this intermittent break of contact 1515 causes de-energization oi the stick relay S and dropping oi the armatures 26 and 35. The armature 26 breaks the maintaining circuit of the stick relay at a second point and prevents it from being re-established, when, after the application magnet has been passed contact 1515 recloses. Dropping of the armature 35 breaks the circuit of the device K and at the same time completes the circuit of the indicating device 38.

If'the controlling zone of the subsequent reset ma 'net R which ma extend one or more blocks) is unoccupied, the traiiic controlled armature 10 is closed and the reset magnet energized. A reset impulse is tran mitted upon passage of the train which causes poles 21 -21 to attract reset armature 19, and to close intermittently the reset circuit. This re-energizes the stick relay S and the device K. After the reset magnet is passed the armature 19 is again retracted by its spring so as to open the contact 1919.

The distance between the application magnet A and the subsequent reset magnet R and the time interval between the de-energization of the stick relay and the starter" a brake application (or other control functions initiated through de-energization of the device K) are so proportioned, that even at the lowest speed, the reset magnet is passed and the reset impulse transmitted before an automatic brake application (or other actuation of the train control apparatus) would take place.

Should, however, the control zone of the reset magnet be occupied the traffic controlled armature 10 will be open, andthe reset magnet R thus deenergized; the application impulse not being new followed by a corresponding reset impulse, the automatic brake application (or other actuation of the train control apparatus) initiated by the tie energization of the device K will take effect.

If the car-carried apparatus represents a plain automatic stop equipment, I also provide a reset switch 43 or similar device {prefera-bly one requiring the train to stop for its operation) to restore the apparatus to normal Wl111,'2tft8l an automatic brake ap plication, the train comes to a stop without passing an energized reset magnet. In case of speed. control the reset device may be omitted.

It should he also noted thatmy invention can be readily applied to the various schemes of forestal ing used in permissive train control systems. 7 1

In Fig. 2 I have shown another embodiment of my invention, whereby the application track element is traiiic contrlled and the reset element permanent, the tra'liic controlledtrack element again succeeding the manent track element.

he application track element is shown as a compound magnet A, comprising permanent magnet bars 4:, soft ironworking poles -5"5 a neutralizing or cancelling coil a l. Such compound magnets are well-known in the art, one construction being fully described in my British Patent No. 1%,922.

The energizing circuit of the coil idincludes the same elements and is controlled in the same way as the circuit of the coil 6 of reset magnet R in Figure 1.

W hen the control zone of magnet A. is occupied, contact 10 is open, coil l4 is de-energized and the flux of the permanent magnet l fully effective. When the track is unoccupied the contact 10 is closed, coil t l energized and the flux of the permanent magnets so diverted as not to have effect on the application receiver eta passing train.

The reset magnet R consists of a permanent "7 and soft iron pole pieces 88.

In this scheme the reset magnet R will have no effect on a train running with the equipment in a normal condition, neither will the application magnet A in case the track ahead is clear and the cancelling magnet l i energized.

Should, however, the track ahead be cccupied, the coil 4% is de-energized and an application impulse is transmitted to the passing train which causes de-energization of the stick relay and of the device K, in the man-- ner previously described.

If the train now'passes a reset magnet the stick relay and the device K will be re-euergized which restores or permits manual restoration of the brake applying means, un-

less the track ahead is stilloccupied, in which case the reset impulse Wlll be closely followed by an application impulse, again de-energizing the relay S and device K. It should be noted that this lay-out of the track devices is more suited for speed control iiystems, than for plain automatic systems. urthermore, the time delay between de-energization of the device K and an automatic brake application can be dispensed with in this scheme.

To differentiate between the action due to the track elements of one character from the action due to the track elements of the other character, I have placed the application track elements and the reset track elements and the corresponding parts of the receiving device in various angular positions, but I do not want to limit my invention to such showing as the same object can be accomplished in other ways as, for instance, by placing one kind of track element closer to one rail than the other kind of track element, and by similarly off-setting the corresponding receivinz devicw.

While I have illustrated the trafiic contmiled track elements as being normally energized, in practice it is preferable to establish the energizing circuit only upon approach of the train. Such arrangement is wellknown in the art and it is not deemed necessary to illustrate it.

In the same way while I have indicated my invention as applied to a double track system with track control only for one direction of traflic, my invention can be equally well applied to single tracks with traflic in both directions. In this case a permanent track element is both preceded and followed bya trafiic controlled track element and for each direction of travel the control rests with the second traflic controlled track element.

It is obvious that various modifications can be made of my system with-out departing from the spirit of the invention. Therefore, without limiting myself to the details shown in this specification, what I claim and desire to secure by Letter Patents is:

1. In an inductive train control system, the combination cf permanently active trackway elements followed in close succession by traflic controlled track elements, said two kinds of track elements being in difi'erent angular positions relative to the rails and located within the rails with vehicle-carried apparatus, said apparatus being inversely influenced by said trackway elements, whereby one kind of trackway element initiates operation of the vehicle-carried apparatus and the other kind of trackway element restrains operation thereof.

2. In an inductive train control system, a pair of track elements in close succession, the first track element being permanently'active and the second element trafiic controlled, the two track elements being disposed in difierent angular positions relative to the rails and centrally located within the rails, effectiveness of an impulse transmitted by the permanent track element being dependent upon an in} ulse transmitted from the traffic cc-ntroll track element.

3. In an inductive train control system, two trackway elements in close succession and in difi'erent positions relative to the rails, the first track element acting independently of traflic conditions, the second track element tral'fic controlled, and locomotive apparatus including a compound receiver to cooperate with both track elements whereby an impulse of the first track element is sub ect to nullification by an impulse of the second track element.

4. In an automatic train control system of the intermittent inductive type, a pair of trackway devices to transmit two kinds of impulses the members of the trackway devices being disposed in close succession centrally between the rails and in different angular relation thereto and car-carried appa ratus comprising automatic brake applying mechanism and means to render one kind of track impulse effective to cause an automatic brake appiication unless said impulse is followed by an impulse of the second kind within a predetermined time interval.

5. In an inductive train control system in combination trackway means comprising a permanently active application track element closely followed b a traflic controlied reset track clement, sai two kinds of track elements being disposed centrally between the rails and in different angular relation thereto and train control apparatus comprising automatic brake applying means, actuation of said apparatus being initiated every time an application track element is passed, said initiation resulting in an automatic brake application only in case of adverse traflic conditions.

6. In an inductive train control system, trackway devices comprising a permanent application magnet closeiy followed by a traffic controlled reset magnet, said two kinds of magnets being disposed in difierent angular relations to the rails and vehicle-carried apparatus comprising a unitary receiver adapted to cooperate with both track magnets, whereby the elfectiveness of an impulse of the application magnet is subject to nullification by an impulse of the reset magnet.

7. In an automatic train control system, trackway elements comprising a permanent application magnet clomly followed by a traflic controlled reset magnet, said two kinds of magnets being disposed in different angular positions relative to the rails and centrally between the rails, and cooperating carcarried apparatus comprising an indicating device and brake applying means, said indicating device being always actuated by an impulse of the application magnet, actuation of the brake applying means being preventable by an impulse of the reset magnet.

8. In an inductive train control system the combination of permanently active track elements followed in close succession by trafficcontrolled track elements, said two kinds of track elements being disposed centrally between the rails and in different angular relations towards the rails, with vehicle-carried apparatus, said apparatus being inversely influenced by said trackway elements whereby the first trackway element always restores the equipment to normal and the second kind of track element initiates operation thereof in case of unsafe traffic conditions.

9. In an inductive train control system, the combination of permanently active trackway elements followed in close succession by traffic controlled track elements, said two kinds of track elements being in different angular positions relative to the rails, with vehicle-carried apparatus comprising a single receiver unit influenced by each kind of trackway element, whereby one kind of trackway element initiates operation of the vehicle-carried apparatus and the other kind of trackway element restrains operation thereof.

Signed at New York, N. Y., this 11th day of June, 1928.

FRANK J ULIAN SPRAGUE. 

